Marcus & Millichap, Inc. Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation Plans - Employee Stock Purchase Plan - Additional Information (Detail)

v3.20.2

Stock-Based Compensation Plans - Employee Stock Purchase Plan - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares available for issuance	4,931,055
Unrecognized stock-based compensation expense \| $	$ 27,219,000
Unrecognized stock-based compensation expenses recognition period	3 years 6 months 29 days
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Length of purchase intervals	6 months
ESPP discount rate	10.00%
Initial Common stock reserved	366,667
Common stock shares available for issuance	188,550
Unrecognized stock-based compensation expense \| $	$ 30,000
Unrecognized stock-based compensation expenses recognition period	1 month 17 days
Employee Stock Purchase Plan - Annual Available for Issuance Share Increase [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for future issuance authorized annual share increase	366,667
Common stock available for future issuance authorized annual percentage increase	1.00%

- Definition

Annual share increase in share reserve allowed under the 2013 Plan.

+ References

No definition available.

+ Details

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- Definition

Represents the length of purchase intervals.

+ References

No definition available.

+ Details

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- Definition

Percentage of available share increase in share reserve allowed under the 2013 Equity and 2013 ESPP plans, calculated as a percentage of outstanding shares.

+ References

No definition available.

+ Details

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Namespace Prefix:	mmi_
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Details

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- Details

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